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b=rNcoS1WGMxWbTfCgU9s9HMtDEldJfjQSSzt/X5zj7pCKbsywSXeWhPJXwyL/yCXcL5zb5FoM/5c+NxdhiwMYLLPLNqfPRQL4u5nDbJiGxsXb8TAB3zNvulqKJXh0hHxv1b97ntOOwFkL6l4que2vyNgHmLGo099VicJnwzmN0Gc= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=amd.com; Received: from DM6PR12MB4202.namprd12.prod.outlook.com (2603:10b6:5:219::22) by SN7PR12MB6714.namprd12.prod.outlook.com (2603:10b6:806:272::18) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9769.15; Mon, 30 Mar 2026 14:26:58 +0000 Received: from DM6PR12MB4202.namprd12.prod.outlook.com ([fe80::9e55:f616:6a93:7a3d]) by DM6PR12MB4202.namprd12.prod.outlook.com ([fe80::9e55:f616:6a93:7a3d%6]) with mapi id 15.20.9769.014; Mon, 30 Mar 2026 14:26:58 +0000 Message-ID: <8737035f-07e9-4c14-93a9-bb542197d7f7@amd.com> Date: Mon, 30 Mar 2026 15:26:41 +0100 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v24 10/11] cxl: Avoid dax creation for accelerators Content-Language: en-US To: Alison Schofield , alejandro.lucero-palau@amd.com Cc: linux-cxl@vger.kernel.org, netdev@vger.kernel.org, dave.jiang@intel.com, dan.j.williams@intel.com, edward.cree@amd.com, davem@davemloft.net, kuba@kernel.org, pabeni@redhat.com, edumazet@google.com, Jonathan Cameron , Davidlohr Bueso , Ben Cheatham References: <20260323113117.2352709-1-alejandro.lucero-palau@amd.com> <20260323113117.2352709-11-alejandro.lucero-palau@amd.com> From: Alejandro Lucero Palau In-Reply-To: Content-Type: text/plain; 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>> >> + /* >> + * HDM-D[B] (device-memory) regions have accelerator specific usage. >> + * Skip device-dax registration. >> + */ >> + if (cxlr->type == CXL_DECODER_DEVMEM) >> + return 0; >> + > And above says 'Skip device-dax' specific again, and is indeed skipped. > > This escape is not surgically placed at the point where dax is added. > We are skipping a few other things before dax registration actually > happens. Why skip memory notifiers, shutdown_notifiers, poison setup? posion setup crashes with a type2 and I'm not sure if the memory notifiers make sense for Type2. If it is really needed, I would prefer to support it as a follow up. Thank you > >> /* >> * From this point on any path that changes the region's state away from >> * CXL_CONFIG_COMMIT is also responsible for releasing the driver. >> -- >> 2.34.1 >> >>